my lips are sealed
US /maɪ lɪps ɑr siːld/
UK /maɪ lɪps ɑr siːld/

1.
我守口如瓶, 我不会说出去
used to say that you will not tell anyone a secret
:
•
Don't worry, my lips are sealed. I won't tell anyone about your surprise party.
别担心,我守口如瓶。我不会告诉任何人你的惊喜派对。
•
She asked me to keep it a secret, and I told her, 'My lips are sealed.'
她让我保密,我告诉她:‘我守口如瓶。’